正常大鼠肝内门－体分流的研究

STUDY OF INTRAHEPATIC PORTAL-SYATEMIC SHUNTS IN NORMAL RAT LIVERS

经大鼠门静脉注射乳胶微球，以完全阻塞肝内的门静脉分支，并观察门静脉压力（ＰＶＰ）的变化。结果表明，门静脉内注射直径为１５或８０μｍ的微球使ＰＶＰ分别增加了１０２．２％和２７２．３％；顺序注射不同组合的微球（１５μｍ＋４０μｍ＋８０μｍ或８０μｍ＋４０μｍ＋１５μｍ）并未使ＰＶＰ获得进一步的升高（分别增加了１６２．８％和１７８．６％）。尽管门静脉内注射乳胶微球可使ＰＶＰ显著升高，但却无法达到肝外门静脉钳闭时的高度（４．８７～５．７５ｋＰａ）。肝静脉楔入压（ＷＨＶＰ）于门静脉钳闭时明显下降，但在注射１５μｍ的微球后却与ＰＶＰ同步升高。所有实验鼠肺内均发现有许多微球。上述结果提示正常大鼠可能存在肝内门－体分流。

Microspheres were injected intraportally to block intrahepatic portal radicals and the changes in portal venous pressurr (PVP) were observed. It was found that the PVP was elevated to a steady state 102.2% and 272.3% above the basal value following the sepuential injection of 15μm and 80μm microspheres respectively. Sequential injection of different-sized microspheres (15μm + 40μm + 80μm or 80μm + 40μm + 15μm) did not induce further increase in PVP. Although the PVP was raised markedly by intraportal injection of larg eamount microspheres, the much higher PVP of 4.87～5.75kPa measured during clamping of the portal vein could not be attained. Moreover, the wedged hepatic venous pressure (WHVP), which always decreases during portal venous clamping, showed a significant increase following the sequential injection of 15μm spheres. Besides, numerous microspheres were found in the pulmonary vascular bed in all of the experiments performed.These results suggest the existence of intrahepatic portal-systemic shunts in normal rat livers.